In recent years, water conservation has taken on increased importance. Many cities and states have passed ordinances dealing with water conservation. Some ordinances relate to the automatic shutting off of faucets that are in public lavatories.
Previous timing devices may have complicated mechanisms that add cost to the faucet valve. The added expense is caused by one spring mechanism for closing the faucet valve and a separate second spring mechanism for driving the escapement device that times the closing of the faucet.
Additional faucet standards have been developed to assure all people, including small children and people with physical disabilities, have full accessibility to public lavatories. One of these standards is directed to the ease of turning on a faucet. For ease of operation, a faucet needs a handle that is shaped to be easily manipulated and operated. Furthermore, the force needed to turn on the handle to the open or on position must not be more that five (5) pounds to assure that the most operators can easily open the faucet and have access to water.
However with many faucets, the manipulation required to open the faucet is different than the manipulation required to close the faucet; i.e., the open motion may be different and easier than the closing motion. For example with blade handles, the opening force may be a pushing motion that is much easier than the reverse pulling motion of the blade for closing the faucet.
A self closing faucet however alleviates the need for manually manipulating the faucet handle to a closed position. The most common way for providing a self closing faucet that incorporates a spring loaded timing mechanism that moves the handle to the closed position.
Previous efforts to simplify the timing mechanism produced handles that were difficult to manipulate and gearing mechanisms that were needlessly driven therefore having premature wear. Secondly, previous faucets could be stuck in an on or full flow position if there was failure of the gearing mechanism and it seized up.
What is needed is durable automatic faucet that is both easy to operate and provides for automatic shutting off of the water and an overriding manual closure capability.